Azo dye for chromed wool and process of making same.



UNITED STATES ATENT Pr on.

HEINRICH OSTER, OF CHARLOTTENBURG, GERMANY, ASSIGNOR T ACTIEN GESELL- SCI-IAF'I F'U'R ANILINFABRIKATION, OF BERLIN, GERMANY.

AZO DYE FOR GHROMED WOOL AND PROCESS OF MAKING SAME.

No Drawing.

To all whom iii-may concern:

Be it known that I, HEINRICH Osrna, a

subject of the German Empire, residing at f Charlottenburg 2, near Berlin, Germany,

(my post-otlice address being Guerickestrasse 14, Charlottenburg 2, near Berlin,) have invented certain new and useful Improvements in New Azo Dyestuffs for Chrome- Mordanted lVool and Process of Making Same, of which the following is a specification.

My invention relates to the manufacture of new azo-dyestufis which are especially adapted for chrome'mordanted wool and may be obtained by diazotizing'2.5-dichloroan'ilin- L-sulfonic acid and combining the diazo-compound thus obtained with an aromatic ortho-ox vcarboxylic acid, such as for instance salicylic acid or ortho-cresotinic acid. The dyestuffs thus manufactured produce on wool in combination with a suitable chrome-mordant orange to red tints which possess a good fastness and a full shade 'overhand.

The following example serves to illustrate my invention, the parts being by weight:

, Example: 26.4 parts of the sodium salt of 2.5-dichloro-anilinl-sulfonie acid are diazotized in the usual manner by means of 50 parts of hydrochloric acid of 12 B. specific gravity and 7 parts of sodium nitrite. The diazo-solution thus obtained is allowed to run while stirring into an aqueous solution of salicylic acid prepared from 14 parts of this acid with the addition of 27.3 parts of calcined sodium carbonate. The combination being finished the dyestuff is precipitated by the.addition of common salt, drained and dried. It is thus obtained in the shape of an orange powder when pulverized which may be dyed on Wool from a dyeath containing Glauber salt and acetic acid, sulfuric acid being added after having boiled for some time, whereupon potassium bichromate is added in order to develop the color. Thus is produced a deep and clear orange tint with a full shade overhand and possessing a good fastness.

. The new dyestuff as above obtained dissolves in water to a yellow to orange solution which on the addition of concentrated hydrochloric acid yields a yellow jelly, whereas by the addition of concentrated caustic soda-lye or of concentrated liquor ammoniae the solution assumes a deep red Specification of Letters Patent. Patented Feb, 15, 1910; Application filed October 21, 1909. Serial No. 523,806.

yellow to orange solution but is insoluble in benzene; in concentrated sulfuric acid it dissolves to an orange-red solution which on the addition of ice separates yellow flakes. The aqueous solution of the dyestuflt' is decolorized at ordinary" temperature by the addition of stannous chlorid and hydrochloric acid, the dyestuff thus being split up, yielding 2.5-dichloroanilin-4c-sulfonic acid besides para-aminosalicylic acid.

It is obvious to those skilled in the art 7 that my present invention is not limited to the foregoing example or to the details given therein. It may be stated, for instance, that if ortho-cresotinic acid is substituted for the salicylic acid, used in the foregoing example, 7 5

and if the conditions of the reaction are altered accordingly, a dyestuif is obtained which in its physical and chemical qualities resembles much 'the dyestufl of the foregoing example; it produces on wool in combination with a subsequent treatment with oxidizing chromium compounds tints which are a little more reddish than the tints of the dyestuff derived from salicylic-acid.

Having now described the invention and the lnanner in which it may be performed what I claim is,-

1. As new articles of manufacture the hereinbefore described new azo-dyestufis which may beobtained by dichloroanilin -4- sulfonlc acid and combining the diazo-con1pound thus obtained with an aromatic ortho-oxy-carboxylic acid, these new dyestuffs producing on wool from an acid bath with a subsequent treatment of oxidizing chromium compounds deep and clear orange to red shades with a full shade over-hand, which new dyestuffs when pulverized are yellow to orange powders soluble in water to a yellow to orange solution which on the addition of a mineral acid separates the free acid of the dyestuff, whereas addition of a caustic alkali changes the color of the solution to deep red, and which new coloring matters are soluble in concentrated sulfuric acid to orange-red solutions from which solutions on the addition of ice the free acid of the dyestuffs separates.

2. As a new article of manufacture the hereinbefore described new azo dvestufl,

diazotizing 2.5- 90 which may be obtained by dia'zotizfing 215'- dichloroanilin-4-sulfonic acid and coinbining the diazo-compound thus obtained with salicylic acid, whlch new dyestuff produces on wool, when dyed from a dye-bath low jelly, Whereas by the addition of concentrated caustic soda-lye or of concentrated liquor ammoniae'the solution assumes a deep red color and Whereas the addition of glacial "atic acid turns the color of the'solution to yellow, this new dyestuff {d'i'$3 1\iii'; in alcohol toa reddish-yellow to"orangc solution and being insoluble in benzene, and this new coloring matter dissolving 'inconcentrated sulfuric acid to'an' orange-red solution which on the addition of ice separates yellow flakes, an aqueous solutioncf'this dyestuff being decolorized at ordinary temperature by the addition'of stannous chlorid and "hydro- .chloric acid, the dyestuii being split up yielding thus 2.5-dichloro-anilin-l-sulfonic acid besides para-aniidosalicylic acid. v

In testimony whereof I have "hereunto set my hand in pr'csence'pf taVoSubscribinQf Witnesses.

Vitnesses:

HENRY l-Lxsrnn, M Wommran HA1: m1.

HEINRICH osricn. 

